Filter



Jan. 13, 1942. s. MALANOWSKI 2,269,725

I FILTER Filed Au 11, 1937 4 Sheets-Shet 2 W Q HMM 1;

Jan. 13, 1942.

s. MALANQWSKI FILTER Filed Aug. 11, 1957 4. Shee'ts-Sheet 3 Jan. 13,1942. s. MALANOWSKI 2,269,725

FILTER Filed Aug. 11, 1937 4 Sheets-Sheet 4 firm/5% @ZHJTUWHU Snow-u,

Patented Jan. 13, 1942 UNITED STATES PATE NT' OFFICE StanieyMala nTwsifTampmFlar Application August 11, 1931, Serial at. 158,455

Claims.

This invention relates to apparatus and material for the rapid andefilcient removal of finely divided matter from various liquids.

In one embodiment of the invention, a device is illustrated for use in asystem in which solvent cleansing fluid is forced in a constant cyclethrough a washing machine in which soiled material is cleaned and thencethrough a tank containing a filter assembly adapted to remove solids insuspension, and grease and other substances in small cuoic space anextremely large surface in solution, whereby the solvent is purified andreturned to the washing machine in a continuous cycle during the washingprocess.

In another embodiment of the invention, a smaller device is shown foruse beneath the hood of an automobile as part of a cyclic oil system toremove from the oil in the crankcase of the engine all solid particlessuch as sand, iron, carbon, and any other material that might cause wearor other interference with the effective operation of the'engine.

As the description proceeds, it will become evident that the inventionis not limited to use with oils or solvents, but is also adaptable foruse with many other liquids which may require clarification ordecolorization, as in filtering beer, wines, and distilled spirits, beetjuice, raw sugar solutions, drinking water and many others.

The primary object of the invention is to utilize the many advantages ofthe dense, stiff, and strong sheets of fibrous material produced bycompression under proper conditions of heat and moisture of wood fiberprepared by explosion from a gun. The disrupted and disintegrated fiberscomprising both fine and coarse particles crisscrossed in variousdirections and formed into boards having two surfaces of relativelydense and strong material united by a central layer of relatively highporosity are particularly well adapted for use as filter units. Incertaincases, these sheets may be used alone, but when the surfacedensity is not sufiiciently great, or where additional effects ofadsorption or decolorization are desired, filter aids, such asdiatomaceous earth, fullers earth, activated carbon, may be added to theliquid passing through the fibrous units to adhere to their surfaces asa highly efflcient clarifying medium which may be removed by a simpleform of scraper at proper intervals to leave a surface on which a newlayer of filter aid may be deposited for continued operation of thedevice without removal of the units from their enclosing casing.

A further object of the invention is to provide to receive the liquid tobe filtered, by arranging a large number of fiat, thin disks with theircenters in axial alinement and spaced apart by relatively thinseparatorazto permit the liquid under pressure to pass through both ofthe dense surfaces of each sheet to the more highly porous central layerwhich acts substantially as a pmrality of tubes'through which it mayproceed to an outlet passage formed within the central portion of theassembly.

As a supplemental object of the invention in connection with the form ofassembly Ju t described is the provision of means for allowing thecompression of the disks and separators to proceed-far enough to make atight joint but preventing compression to an extent that will undulylimit the passage of filtered liquid.

Another object of the invention in connection with the same form of diskand separator assembly is the provision of means for mounting the filterdisks for rotation while maintaining interposed scrapers stationarytoremove filter aid and dirt, and the provision of additional means fordirecting the refuse after it has been scraped from the disks to anoutlet from whiclr it may leave the filter casing.

In the drawings, Figure 1 is a vertical section through the center of astorage tank and filter chamber particularly adapted for clarifyingliquids used in dry cleaning; Fig. 2 is a horizontal section on a largerscale through the filter tank of Fig. 1; Fig. 3 is a fragmentaryvertical section showing details of the upper end, and Fig. 4 is afragmentary vertical section of the lower end of the filter assembly ofFig. 1; Fig. 5 is a vertical section taken longitudinally of anotherembodiment of the invention in which filter disks are mounted invertical planes; Fig. 6 is a vertical section on the line VI-VI of Fig.5; Fig. '7 is a vertical section through a modification of the structureof Fig.- 1; Fig; 8 is a vertical section through the casing of an oilfilter for automobiles, with the filter assembly shown partly inelevation and with parts broken away and in section; Fig. 9 is atransverse section through the tube used to supply filter aid in thedevice shown in Fig. 1; Fig. 10 is a fragmentary section on a smallerscale of the parts shown in Fig. 3, the sections of the two figuresbeing in planes at right angles to each other; Fig. 11 is a fragmentaryelevation of the central part of a filter disk and of a separator havingthe'construction shown in Fig. 5; Fig. 12 is a fragmentary sectionthrough parts of four filter disks and three interposed separators,showing the mounting of a tie 13; Fig. 15 is an elevation and Fig. 16 isa transverse section of a filter element of thefamiliar type shown inpatent to Heckman, 2,041,763, May

26, 1936; Fig. 17 is an elevation of a modified form of the samestructure; and Fig. 18 is a fragmentary section'through a preferred formof fiber board used in the preparation of filter elements.

The structure illustrated in Fig. 1 is similar in many ways to thatshown in patent to Malanowski, 2,024,463, December 17, 1935, both havinga storage tank I in which is mounted a filter tank capable of receivingits fluid to be clarified either from the storage tank or from anoutside source, as a washing machine, and the filter tank having twodischarge outlets, one leading to the storage tank and the other to anoutside place of delivery.

In the present device, the storage tank I has a bottom 2 having acentral opening for the reception of a pipe 3 formed at the lower end ofthe conical bottom of the filter tank 4. As best shown in Fig. 4, thetank 4 rests upon a washer 5 and a gasket 6, and the pipe 3 is held inplace by a nut 1 having a washer 8 and gasket 9 interposed betweenit'and the tank bottom 2 to form a liquid-tight joint. A valve III isprovided for normal closure of the pipe 3. Near its upper end, the tank4 has an inlet pipe communicating with a filter aid chamber l2 into thelower end of which discharges a pipe l3 leading through the tank bottomfrom a pump l4. Within its lower end, the tank 4 has a fitting l5secured to the wall of the tank on one side by a pipe l6 and on theother side by a brace member or members H. The pipe IE on the outside ofthe tank 4 leads to a three-way valve l8, which in one positiondischarges into a pipe I9 leading to a washing machine, as in thepreviously mentioned patent to Malanowski, or elsewhere, as desired. Thetank 4 maybe secured to the tank I by a plurality of braces ll of whichthe terminals are indicated in Fig. 2, these braces being omitted fromFig. 1.

In the top of the fitting I5 is secured a sleeve or bushing 20, which issecurely attached to the bottom of a tube 2| having a group ofperforations 22 in its lower end as indicated in Fig. 4.

At the upper end of the tube 2|, is a plug 23, having an axial passagefor a rod 24, to the top of which is welded or otherwise secured a crossmember 25, shown in Fig. 3 as formed of a U-shaped channel piece ofsuflicient length, as shown in side view in Fig. 10, to engage the endof a screw or screws 26 projecting through the side walls of a sleeve30. The lower end of the rod 24 is rotatably mounted within a bushing 28secured within the lower surface of the fitting l5 coaxially with thetube 2|. Two arms 29 extend in opposite directions from the lower end ofthe rod 24, each arm having a plurality of pins projecting therefrominto close proximity to the conical bottom of the tank 4.

A cap 21 is shown in Fig.3 secured by screws 26 to the sleeve 30, theinside diameter of which is slightly larger than the diameter of theupper end of the tube 2| which extends into the lower end of the sleeve.Upon opposite sides of the sleeve 20, are welded or otherwise securedrods 3|, which at their other ends are also welded or otherwise securedto a sleeve 32, externally threaded to receive a threaded flange member33. The cap 21 has a. flange 34.

Between the flange of member 33 and the flange of the cap 21 are mounteda plurality of circular, flat, fibrous filter elements 35 spaced fromeach other by circular, flat spacers 38, each of which is surrounded bya metallic hub or ring 31 irom'which curved scrapers 38 extendoutwardly, with their outer ends beyond the outer edges of the filterelements. The scrapers 38, as shown in Fig. 2, arch outwardly from thehub with the scraping edges approximately tangent to the hub at theirinnermost ends and at about to the radius from the center at the pointat which they leave the edges of the disks. The angle of contact of thescraping edge with the direction of movement of the surface of the diskgradually increases from the hub outward and any material adhering tothe surface of the disks is thus thrust outward away from the hub. Thisarched construction greatly adds to the resistance of the scrapers tosidewise bending. As best shown in Fig. 21, these elements 35 andspacers 36 have central openings larger in diameter than the-tube 2|,with notches in opposite sides of the openings in the elements 35 forengagement with the rods 3|. The sleeve 30 is shown in Fig. 3 as smallerthan the opening in the elements and spacers to permit them to be placedon the rods 3| from the top before the cap 21 is secured in place by thescrews 26. The bushing or sleeve 32 is also smaller in diameter than theopenings in the disks and separators, so that before the flanged member33 is secured on the sleeve 32, the disks and separators may be placedon the rods from the bottom also, as may be more convenient.

When the filter members, spacers and scrapers have all been placed inorder upon the rods. the flanged member 33 may be screwed upon thesleeve 32 to clamp the assembly securely together between the flanges atthe opposite ends with the spacers closing the sides of the centralopening between the disks, and the cap 21 closing the upper end. Theassembly so formed may be handled as a unit to place it upon the tube 2|with the lower surface of the member 33 resting with a ground joint uponthe upper surface of the fitting IS. The lid 39 of the tank 4 may thenbeplaced in position and clamped tight by nuts 40 engaging studs 4|around the upper rim of the tank. A gasket 42 in an annular ring member43 welded within the upper rim acts to form a liquid-tight seal for thetank lid. Mounted centrally of the lid 39 is the stem of a hand crank 44which canrotate in a gland or stufllng box 45 secured upon the lid bythe nut 45. At its lower end, the crank has secured thereupon a springpawl member 41 adapted for engagement with a pair of lugs 48 securedupon opposite sides of thecap 21. These lugs are beveled at the top asshown at 49 in Figs. 3 and 10, so that if the crank is rotated in onedirection, the ends of the spring 41 will ride up the bevels withoutturning the cap, but when turned in the opposite direction, the springends will engage the vertical sides of thelugs and cause rotation of thecap, the sleeve 30, the rods 3|, and thus of the whole assembly aroundthe tube 2|, the

weight being carried by the member 33 and the fitting I5.

At the bottom, the tube 2| fits closely within uie'sie'ev as a the top,it fits closely within v the sleeve. 30, thus iorminga vertical journalon fwhic'h the. assembly can. be turned freely with no sidewisetiltingiAs the cap-turns, the inner projectingends of the screws 26 will engagethe crossbar 25 to turn it around on'the upper surface or the plug 23and the suspended'rod 24 with its arm s "Twill be, 'tumed about itsaxis.

-A- flange ills-secured onthe inner wall of the tank 4 on each side for;engagement with the oDpOSite ends of the scrapers to prevent theirrotation as the filter arje'turned. Any solid matter adheringto thesurfaces of .the disks will thus be'thru'st'iagainstthe scrapers andwill slide outward; along the curved sides-of the scrapers to the outer'rim of the disksrwh'ere it will-fall downward throughthe I space 7between the tank in the chamber [2.1 Fluid forced by the pump l4 upthrough the pipe "into the chamber I! will wash the filter aid alongwith it. and as the liquid enters the spaces between the filter disksfollowing the paths of least resistance, the filter aid will bedeposited over the surfaces in accordance with they amount of liquidentering at any point until the resistance is substantially uniform overthe whole assembly.

'Difierent filter aids, will be used for different liquids having thephysical and chemical properties best suited in each instance to theliquid to be treated and in accordance with the size 'of the particlesto be removed. Because of the relatively high densityof the smoothsurfaces formed by the action of heat and pressure on such boards,

wall andthe disks in'tothe conical bottom, on

' patent to Mason, 1,663,504, dated March 20, 1928,

though it'w'ill be'understood that this invention is not limited to anyspecific process of manufacture or to any specific form of fiber. Aboard of compressed. fiber having suflicient coherence and rigidity tomaintain itself in a liquid of the kind that is to be filteredwithouttoo great warping or swelling such as to 'aifect its efiiciencyfor its intended use, and having a constituent mass of fibers permeableto the liquid but 'dense'enough to stop and hold the filter aids thatmaybe required by the condition of theliquid may be formed into, a 'filterelement such as has been described, and the separators may also in somecases be formed of the same material because it so readily forms aliquid-tight joint beween the filter elements, and is at once light andinexpensive. The spacers may, of course, be made of a differentmaterial, if desired.

The main tank I which surrounds'the'tank 4 has a cover member 5| with"three openings. The central opening hasv a collar 5 2',-,pr eferablyofonly. a little greater diameter than that 'of the cover or lid 39 toprevent objects irom'sliding off the cover into the storage tank, A fiatcover only a small amount of filter aid will be'required as comparedwith filters using bags and metallic screens. The ease of cleaning thefilter elements. of removing the sludge, and of applying the filter aid,are important features of the invention, while the efliciency offiltration is very high.

While the present invention is not primarily concerned with details ofarrangements of pipes.

valves, and tanks, an outlet pipe 62 is indicated forming an outletpassage controlled by a quickaction valve 63 to enable the operator todrain the main tank into anunderground tank rapidly when desired, or,with other valves (not indi cated) closed, liquid from the tank I may bewithdrawn through the valve 63 and forced by the pump l4 through thefilter and out through pipe I9 to a washer, as shown in the previous'Malanowski patent cited, from which it may be returned through the pipe64 to the pump for further passage'through the filter.

Since the filter elements are the only parts of the device. which arelikely to'require replacement over long periods of use, and since thepreparation of the assembly requires a certain skill, a special form ofprotective casing has been devised in which the entire group of filterelements can be enclosed at the factory and shipped in a relativelylightcarton to the place of use, where the casing may be left in itsentirety, and the whole assembly can be placed upon the tube 2| withinthe casing 4.

Such a-modification is illustrated in Fig. I, in

Whichthe parts 4, H, l5, l6, I1, 21, 35, and 3' to '48 inclusive areidentical in structure and function with the correspondingly numbered 7parts in Figs. 1, 2, 3, and 4.

The metallic casing 65 is formed as a cylinder 53 rests upon the collar52 with anyform of-con nection desired to hold it'in place, nonebeingwith a flanged top 66 and a flanged bottom 51 secured, as bywelding within the ends of the cylinder. A series of perforations 68around the Y top andbottom permit the entry into the casing shown. Asmaller opennig in the cover- 5|; .ad-

mits a'key or handle 54 for the valve [8, and. a

somewhat larger opening has a collar 55 surroundingthe fitting 56 at the.upper end of the of the'cha'mbei- [2. This tube may-be withdrawnfromthe chamber by engaging a finger under a cross-pin Bl'in' the upperend of the tubes The thin-metal of the tube'will yield and spread a thepowdered matter will enter at the top, while of fluid under pressurefrom the tank 4. A baffie plate 69 opposite the intake pipe I l directsthe-fluid and filter aid upward so that most of 1 any that settles downbetween the casing and the littleas it is thrust into a mass of powderedsolid filter aid,-which will beretained by the elastitfi ty, @of thetubewhile it is lifted and set into-position tank wall will be drawn in atthe bottom holes.

The flange on the cap 21 will be modified to pm vide stepped concentricflanges, of which the upper and smaller engages within and centers thecentral perforation in the casing top 66, while the lower step acts as asupport on which the casing hangs suspended so that its bottom member isjust out of engagement with thelowersurface of the lowermost filter disk35. Flanges 5r on the inside of the casing act as stops for thescrapers: 38. Any suitable means may be used to preventtrotation of thecasing within the tank 4.

tank is shown as a cylinder having its axis sethorizontally and havingtwo' outlet openings ll controlled by gate valves 12 which dischargeinto a sludge tank .13. An inlet opening 14 at the top of the tank has acuplike receptacle I2 provided .with a threaded cover". A loose, fiatsheet metal false bottom 16 having. peripheral Openings I1, rests withinthe receptacle to hold powdered filter aid 18, this false bottom actingto prevent the powder from falling in a mass into the pipe until it iswashed in by the liquid to be filtered entering through intake pipe I8.

As best shown in Figs. 11 and 12 the filter disks 80 and the separators8| have a central opening 82 adjacent to which are a plurality ofperforations of a size in the separators to receive rods 83, andsomewhat larger in the filter disks to receive metallic bushings 04having an inside diameter sufiicient to permit free passage of the samerods 83. The ends of the rods are threaded to receive nuts". Ateach endof the assembly, I

flanged members 80 have-perforations 'to receive the ends of therodsafter the disks, separators and scrapers have been assembled withthe rods passed through the perforations, and by tightening nuts" on therods until the ends of the bushings engage firmly against theseparators, the disks willbe sufliciently compressed to forma tightjoint with the separators but not enough to prevent free passage ofliquid from the disks into the central passage formed by theopenings 82.

In each end of the tank 70 is secured a sleeve member 81 having aportion within the tank of a stead of in two directions as do thescrapers 88 illustrated in Fig. 2. The outer ends or the scrapers engageagainst a lip I04 shown in Fig. 6 as formed by rolling outwardly thefree edge of the sheet metal which constitutes one side of thesubstantially cylindrical metallic casing III. This casing has two suchside members, as best seen in Fig. 6, which are connected at their endsby caps I08 having flanges preferably turned inward as shown in Fig. 5.

As in the modification shown in Fig. 7, in which the casing 85 serves asa protection for the filter elements during shipment, so in the presentembodiment, the casing I05 also acts as a carton for the shipment of thefilter assem bly. It will readily be understood without illustrationthat the opening I01 which runs lengthwise of the casing opposite theinlet opening 14, and also the opening I08 which runs longitudinally ofthe casing opposite the outlet opening 'II may readily be covered duringthe shipment by removable strips, as for example flanged metal stripswhich may engage the lips I04, as by sliding longitudinally thereon.

In assembling the elements within the casing, the scrapers will be set,so that the ends all lie within the opening I08 which will be placeddownward whenthe casing is slid into the tank size to fit closely butyet rotatably within the flanged member 88 adjacent thereto. An end 88may be welded or otherwise permanently secured to the outlet end of thetank, and to the sleeve 81 at this end will be connected the dischargepipe 08. At the other end of the tank, the end The friction of theelastic lips I04 onthe sides of the tank 10 will be suflicient toprevent rotation of the casing I05 within the tank 10. The ends of thecasing, indicated at I06 in Fig. 5, will have. central openings to fitupon the exterior of the, sleeves 81, so that the entire filterv diskassembly may be turned by the handle I00 in one direction, preferablyclockwise, when the notch 98 engages the pin 99, but if the handleisturned in the reverse direction, the sloping side of the notch willslide off the pin 89. As the disks are rotated, their sides will beengaged by the lateral edges of the curved scrapers I03, the archedshape of these scrapers serving to strengthen .their resistance to thepressure exerted upon member a will bear against a gasket 9| held achannel member 92 secured within the inner periphery of the end. of thetank 10. A plurality of clamp rods 93 having end nuts 94 toengagefagainst sleeves 95 welded upon the end cover members and 80 serveto secure the cover 80 in place. Tubes 86 of the same diameter as thesleeves 95 surround the rods between the sleeves 85, for the sake ofappearance.

The sieeve member 81 within the end 90 has slidably mounted therein acylindrical element 91 having a notch 88 in its end adapted to engage inone direction of rotation with a crosspin 88 secured at its ends withinthe member 86. One side of the notch is shown as at right angles to theplane of rotation of the pin while the other side slopes outward fromthe bottom of the notch. The member 81 is provided with a handle I00extending through the stufilng box IM to prevent the escape of liquid.By the use of this hand crank, the filter assembly may be rotated as aunit upon the inwardly projecting terminals of the sleeves 81.

Surrounding the separators 8| are the hubs III of the scrapers I03 ofwhich one is shown in Fig. 6. It will be seen that in this form of theinvention, the scraper extends in one direction only from the axis ofthe filter assembly, in-

them by the adherent dirt and filter aid upon the surfaces of the disksrotated toward them.- As this dirt is loosened, it will fall downwardimmediately along the front surface of the scrapers into the space I08between the two lower lips I04. Around the outer edge of each filterdisk is a metallic band I09 (Figs. 13 and 14) upon which is secured asby spot welding, a plurality of vanes IIO set at an angle to the planesof rotationoi the disks to which they are attached, this angle for anydisk being such as'to cause the vane to push the sludge toward thenearest outlet II. The valves 12 will be opened before this cleaningprocess is started and the heavy solid matter will pass rapidly downinto the tank 13. It will be noted that the dirt will adhere equally toboth sides of each disk, since the suction will be uniform atsubstantially all points of the disk, and when the adherent dirt isdetached, it can fall less than half of the diameter of a disk to thebottom without interference from dirt from any other disk, and a singlerotation of the assembly will move all the sludge the short distance'necessary for it to reach an outlet. When the above the sludge throughanother petcock I2 set in the upper part of the removable end capthrough which the sludge may be taken out after it has settled. Rotationof the cap slowly will lower the petcock I2 so that practically all ofthe liquid above the solid matter can be withdrawn before the cap isremoved. A valved bypass tube 8'I is provided to allow the escape of allair from the top of the tank ID as it is being filled with liquid. Theliquid will rise in the tank and in the pipe 89 simultaneously and allair will escape before any liquid flows out of the pipe 89, whereuponthe valve in the bypass will be closed to prevent the passage ofunfiltered liquid.

The embodiment shown in adapted for use as an oil filter forautomobiles. It comprises a metallic casing having a cylindrical bodyIII and two end caps H2 and II 3, either of which may be made integralwith the body or permanently secured thereto. In the present embodiment,as illustrated, the lower end cap II2 has a tube II4 welded theretocentrally of one end, this tube being of a length to extend beyond theopposite end of the body to receive the cap II3 which is centrallyperforated to engage upon the end of the tube. The cap H3 is shown ashaving a flange around its edge to rest upon a gasket I I5 which isengaged upon its other surface by a flange I I6 on the end of thecylindrical body wall III. A nut I I1 threaded upon the end of the tubeII4 serves to clamp the cap H3 firmly in position on the gasket II5.Within the body, the tube II4 receives a bottom supporting pad II 8 onwhich rests a filter disk H9 and then a separator member I followed byalternating disks and separators for the length of the body, the topmostmember being another pad I2I similar to or identical with the pad H8,these two pads at top and bottom being made of a thickness such thatwhen the nut is turned down tight upon the cap I I3 no oil can pass theassembly unfiltered. Near the bottom, the tube I I4 has perforations I22to permit oil to enter the tube on its way tothat the disks II 9 and theseparators I2 haveeach a central opening similar to that shown in Fig.11 in the disks 80 and separators 8|, while the opening in the pads H8and I2I is just sufiicient to let them go on the pipe II4. An inlet pipeI26 admits oil into the casing and this oil must pass through some oneof the porous ele-.

ments to reach the outlets, since the pads seal the two ends of theassembly. and the separators effectively close the spaces between thedisks. A plug I21 is used to close the upper end of the tube 4 wi hinthe nut. v

In this embodiment of the invention, no scrapers are used and hence nomeans for rotat- Fig. 8 is especially ing the disks needs to be providedor any outlet 1 for sludge. The tube II4 serves as an outlet for oil, asa part of the means for clamping the cover in place, and hence as a partof the means for clamping the filter assembly together. When the filterbecomes covered with dirt to a point.

where filtration is too greatly retarded, the nut II'Iwill be released,th filter disk assembly will be removed and discarded, and a newassembly will be inserted. The cost of replacement will be too small tomake it worth while to clean the used elements.

In certain types of filters such as that shown in patent to Heckman,2,041,763, above mentioned, a plurality of fabric filter bags are usedwhich have many disadvantages. As a replacement unit for this form offilter element, Figs. 15 and 16 illustrate a sheet of rigid, coherent,fibrous material I28 having a slot I29 cut for somewhat over half of itslength, this slot being covered by a sheet metal member I38 rivetedalong its sides to hold it in tight contact with th surface of the sheetI28, the outer end of the member I30 being formed into a tapering tubeI3I for insertion into the tapering sockets of a manifold as well knownin the art and specifically shown in the Heckman patent cited. Liquidunder pressure in a container in which such a filter element is mountedwill pass through both surfaces into the porous interior longitudinallyof the interior to the outlet passage or slot I29 leading to themanifold. A similar device is shown in Fig. 17, in which the metallicmember I32 extends around the edges of the sheet instead of through thecenter, the liquid in this device passing outward from the central partof the sheet to the channel formed between the edges of the sheet andthe metallic strip that leads to the tapering tube I 33.

As shown in Figs. 2 and 6, the edges of the double scrapers 38 and thesingle scrapers I83 which engage with the sludge on the surfaces of thefilter disks are formed as curves which at their innerends aretangential with the hubs 39 or I02 and which extend outward in thedirection of rotation of the disks toward the rims, being at a greaterangle than 45 to the radiusfrom the center to where they cross the rim.Thus as the detached solid matter slides along the scraper, it is pushedoutward from the center. If the scraper were set radially, the matter onthe disk would pile up between the disks and make rotation of the diskssubstantially impossible.

The constructions shown are to be considered as merely illustrativesince it will be evident that many changes in the form, proportions,number of elements, and other details of construction may be madewithout departing from what is claimed. 7

I claim:

1. A filter comprising a container for liquid under pressure, a filterelement consisting of a stiff, self-supporting, coherent, substantiallyhomogeneous body of fibrous material, permeable to liquid in alldirections but of a density such as to prevent the passage of finelydivided filter aids, said element being mounted within said containerwhereby to permit the deposit of filter aid upon its surface exposed tothe liquid under pressure, and said element being provided with apassage connected with its interior and communicating with the exteriorof the container to permit the outlet of filtered liquid.

2. A filter comprising a plurality of sheets of rigid, coherent,cellulose material, a perforated tube communicating with the exterior ofthe filter on which said sheets are mounted, separators of smallerdiameter than said sheets surrounding the tube and interposed between'adjacent sheets whereby to expose both surfaces of said sheets toliquid under pressure to be filtered, the sheets and separators havingportions thereof removed to provide a passage for the tube .01 greaterdiameter than the tube, arrangement being such that liquid in contactwith said sheets will enter both and pass longitudinally of said sheetsand through the I perforations in the pipe.

3. A filter assembly comprising a plurality of the" fibrous sheets, aplurality of spacersofsmaller diameter than the sheets and interposedbetween the sheets to hold them in spaced relation, the

sheets and the spacers having a passage for liquid formed therethrough,a flanged member at each 3 end of the assembly ,of sheets and spacers,rods passing through said spacers, and connecting said flanged members,and means for placingrthe rods j under tension to compress'the sheetsbetween the spacers. 1

4. A filter assembly as in claim 3, in which the sheets havebushingssurrounding the rods, with rigid, coherent, cellulose material,separators of smaller diameter than said sheets interposed betweenadjacent sheets whereby to expose both surfaces or said sheets to liquidunder pressure to be filtered, the sheets and separators having portionsthereof removed to provide a passageway therethrough, means to hold saidsheets and separators with said passageways in alinement to rorm acontinuous conduit for collection of filtrate, the arrangement beingsuch that liquid in contact with said sheets will enter both surfacesthereof to pass longitudinally of said sheets into i said filtrateconduit, a. casing to enclou the assembly of sheets and separators andto retain the fluid surrounding the same, an inlet and an outlet formedin said casing, said inlet being in com- 'munication with a body 01'fluid surrounding said the ends of the bushings in engagement with thespacers to limit the amount ofcompression 7 of the sheets.

5. A filter comprising a'contalner for liquid under pressure, aplurality of filter disks mounted for rotation within the saidcontainer, a plurality of spacers of smaller diameter-than the "disksand interposed between the disks to hold them in spaced relation, ascraper interposedbetween I two adjacent disks, means for preventing thescraper from rotation, means for rotating said disks, and vanes upon theperiphery of the disks set at an angle to the plane of'said disks 'andmovable adjacent to the bottom of the tank to move material scraped fromthe. diskssidewise' horizontally toward an tainer.

6. A filter comprising a container for liquid outlet from the conunderpressure, a plurality of filter elements mounted for rotation on ahorizontal axis, scrapers interposed between the said elements to detachrefuse material from the surfaces or said sheets and the outlet being incommunication with the filtrate conduit formed by the passageways insaid sheets and separators.

9; A filter comprising a plurality of sheets of rigid, coherent,cellulose material, separators of smaller diameter than said sheetsinterposed between adjacent sheets whereby to expose both surfaces orsaid sheets to liquid under pressure to be filtered, the sheets andseparators having portions thereof removed to provide an open and passlongitudinally 01' said sheets and into elements when they are rotated,an outlet in the bottom of the container to receive. the refusematerial, and vanes upon the periphery of saidfilter elements adapted toengage the detached refuse and move it toward said outlet. I

7. A filter comprising a plurality of filter disks having substantiallyparallel surfaces and mounted for rotation on an axis, a plurality ofspacers interposed between said disks to hold them in spaced relation, aplurality of scrapers each having a hub surrounding and closely adjacentto one of said spacers and extending outsageway thru each sheet,separators of smaller said tube, thence away from said casing, means forcompressing said sheets and separators togethcr to prevent leakagetherebetween.

- 10. A filter comprising a plurality of sheets of rigid coherentcellulose material, a drainage pasdiameter than said sheets interposedbetween adjacent sheets whereby to expose both surfaces of said sheetsto the liquid under pressure to be filtered, drainage passagewaysthrusaid separators to register with the drainage passageways .in saidsheets, the arrangement being such that wardly from said hub toward theperiphery of said disks, the scraping edges of said scrapers lyingclosely adjacent to the surfaces of the adjacent disks and beinginclined in a curve extending outwardly from the hubs in the directionof rotation of the disks and at a gradually increasing angle thereto,whereby to thrust solid matter on the surfaces of said disks away fromthe axis of rotation. T i

8. A filter comprising a plurality of sheets of liquid in contactwith'said sheets will enter both surfaces thereof and pass longitudinally ofsaid sheets into said passageways, a casing to enclose said sheets andseparators including means to compress the same into the form of acrenelated filter column having a continuous passageway therethru forthe collection of filtrate, an

outlet opening in said casing in communication with the passageways thrusaid elements and separators, and an inlet opening adapted to conductthe fluid to be filtered into said casing.

STANLEY MALANOWSKI.

